(9RS)-3-acetyl-9-ethyl-1,2-dihydro-9-hydroxy-4-methyl-3H,12H-pyrano<3',4':6,7>indolizino<1,2-c>benzo<2,7>naphthyridine-10,13(9H,15H)-dione                                                                                                                                                              在
                                                                                                                                                                                 
盐酸                                                                                                                                  作用下,
                                                                                                                                                                                        反应 1.5h,
                                                                                                                以33%的产率得到(9RS)-9-ethyl-1,2-dihydro-9-hydroxy-4-methyl-3H,12H-pyrano[3',4':6,7]indolizino[1,2-c]benzo(ij)[2,7]naphthyridine-10,13(9H,15H)-dione